Liam Gallagher's last-gasp two-pointer sent London home victorious from Semple Stadium as Tipperary fumbled their opportunity to go top of Division 4.
The sides were level seven times in an even contest with Thomas Lenihan equalising for the Exiles in the second added minute.
Gallagher’s winner was initially ruled a one-pointer but even though the orange flag wasn't waved, it was upgraded to two upon the final whistle.
Having defeated Wicklow, London’s second win now pushes them into the promotion conversation.
It took a while for the new rules to make an impact on their first run-out at Semple Stadium.
Micheál Freaney kicked the opening score in the eighth minute and Tipp soon pushed on with a five-point burst.
Mark Russell landed one and then blocked down a London two-point attempt. With the goalkeeper caught upfield, Michael Barlow took a shot at the goal from the 45 but his effort bounced over for a two-pointer.
Mark Stokes had a shot saved by Andrew Walsh before play was called back for a Seán O’Connor free.
In the 22nd minute, London were back in the game. Ciarán Diver took the ball on the loop and under pressure, lofted his shot into the top corner.
They struck again in the 28th minute as Kristian Healy knifed Tipp open and laid a pass on a plate for Shay Rafter to palm home.
That made it 0-07 to 2-01 and London kicked the final pair from Tighe Barry and Gallagher to lead at half-time.
Tipp hadn’t scored from play for 27 minutes and counting but an O’Connor two-point free brought them back level, 0-11 to 2-05.
Diver’s second point in a row edged London back ahead but when Cian Smith ended Tipp’s scoring drought from play after 35 minutes, they were level again.
Tipp ended with 13 wides and didn’t lead until six minutes from time when Russell curled over a sweet two-pointer but it didn’t last.
Tipperary: S Ryan; M McFadden, J Feehan, J Harney; T Condon, L Boland (0-01), M Stokes; C Deely, M Russell (0-03, 1tp); J Nevin, M O’Shea, M Freaney (0-01); C Smith (0-02), M Barlow (0-02, 1tp), S O’Connor (0-08, 1tp, 5f).
Subs: E Moloney for Harney (35, inj), B Comerford for Freaney (h-t), P Feehan for Nevin (41), D Brennan for Barlow (58), K Costello for Condon (63).
London: A Walsh; S Taylor, D Rooney, N McElwaine; E Walsh, C Gallagher, A McLoughlin; L Gallagher (0-04, 1tp), T Barry (0-02); J Obahor, D Clarke, K Healy (0-01); P Dolan (0-01f), S Rafter (1-01), C Diver (1-03).
Subs: DJ O’Flaherty for Obahor (43), T Lenihan (0-01) for Dolan (54), S Tucker for McLoughlin (60), M Walsh for C Gallagher (63).
Referee: C Ryan (Galway).
